1. Field
Embodiments relate to a power management system for informing a user of power rates transferred from a power provider, and a method for displaying the power rates.
2. Description of the Related Art
With the development of Information Technology (IT), the number of household appliances powered by electricity is rapidly increasing, in turn leading to increasing power consumption. In order to satisfy such increased power demand, the number of power plants is rapidly increasing. However, as can be seen from a power demand pattern, peak capacity is not reached during most days of the year, that is to say, power plants only operate at full capacity during a few days out of the year.
A status in which a high power demand is required for a short time is called peak load. During periods of peak load, electricity costs the most to generate and deliver, and therefore power providers raise the power rate charged to consumers during periods of peak load. Construction costs for adding an additional power plant to the grid are extremely high and maintenance costs for power plants constructed to maintain peak load for a short period are considerable.
Recently, numerous developers are conducting intensive research into a demand management method for temporarily restricting power consumption by limiting peak load without constructing such additional power plants. For the aforementioned purposes, demand management is a focus of attention, and a great deal of research is focused upon an advanced demand management format for demand response (DR).
DR is a system for intelligently managing energy consumption depending upon variation in power rates. For example, the consumer may temporarily stop an air-conditioner so as to reduce power consumption when power rates are high.
By means of the DR, a power-supply source can alter user power consumption to achieve load balancing and can restrict user power consumption to periods when demand is low, thereby reducing the user's overall energy expenditure.
Therefore, an energy management system (EMS) to which DR is applied has been developed. The EMS receives current power rate information from the power provider, displays the current power rate information on a display, and turns an electric device on or off on the basis of the current power rate information.
The EMS displays only the current power rates, such that the user has difficulty in recognizing a level of the current power rates. In addition, the EMS is unable to predict the future power rates and the degree of variation in power rate levels, such that it has difficulty in effectively driving an electric device on the basis of power rates.